I need to keep my contacts in sync across several devices: smartphone, dumbphone, PC, and also have access to them on the web from any connected device.
What would be the best way to achieve that ?
I use a service called MemoToo and you can check out how I set it up on my blog.
If you go to http://memotoo.com and setup an account you can have your contacts synced with tons of services including:
Its also ver cheap and you only need to pay £12 per year if you have more than 50 contacts. I have 2000+ and it work just fine.
Apart from google and ovi service - here are a few more...
Mobile me works with IPhone, IPad, Mac and PC - so useful for Apple related hardware.
You could use Microsoft Phone Data Manager which syncrhonises data from a variety of mobile phones and a PC.